James Wright Foley, kidnapped journalist, apparently executed by ISIS

(NBC NEWS) -- The Islamic State of Iraq and al-Sham (ISIS) claims to have beheaded an American photojournalist and has threatened the life of another American journalist if President Obama doesn't stop airstrikes in Iraq.

A graphic video obtained by NBC News purportedly shows James Wright Foley, a freelance reporter for the U.S.-based news service GlobalPost who was kidnapped while reporting from Syria two years ago, reciting threats against America before he is executed by an ISIS militant.

The terrorist video shows footage of Obama speaking from the White House on the day he told Americans he had authorized airstrikes in Iraq.

Foley was kidnapped at gunpoint near the town of Taftanaz in northern Syria on Thanksgiving Day in 2012. He had not been heard from during his time in captivity. "We've heard nothing. Nothing. We last knew that he was abducted on Thanksgiving Day in the Idlib province, but we don't know who took him or why," Foley's father, John, said on TODAY last year.

The terrorist video shows footage of Obama speaking from the White House on the day he told Americans he had authorized airstrikes in Iraq.

Foley, a native of Rochester, New Hampshire, traveled extensively in the Middle East and North Africa. He reported about conflicts in Iraq, Afghanistan, and Libya, where he was once held captive for 44 days.

In May 2011, Foley recorded a video interview with The Boston Globe about his arrest and captivity in Libya. "You don't want to be defined as that guy who got captured in 2011," he said. "I believe that front-line journalism is important."

In the video, ISIS claims they are holding a second journalist, Steven Joel Sotloff. After the apparent beheading, an ISIS fighter stands next to the man identified as Sotloff and declares: "The life of this American citizen, Obama, depends on your next decision." Sotloff, a freelancer who worked for several news organizations, disappeared in Syria in August 2013.

In a message posted on the Facebook page "Free James Foley," Foley's mother, Diane, said she was proud of her son and asked for "privacy in the days ahead."

White House National Security Council spokeswoman Caitlin Hayden said in a statement that the "intelligence community is working as quickly as possible" to determine the authenticity of the terrorist video. "If genuine, we are appalled by the brutal murder of an innocent American journalist and we express our deepest condolences to his family and friends," she said.

In a statement published on the GlobalPost website, CEO and co-founder Philip Balboni said the organization appreciates "all of the messages of sympathy and support that have poured in since the news of Jim's possible execution first broke" and asked for "prayers for Jim and his family."